The black liquid that was video recorded being dumped into the sea near Fort Ricasoli in Kalkara.

The authorities should insist the oil treatment facility caught dumping a black liquid in the sea earlier this week should introduce stricter controls, marine biologist Alan Deidun said.

The mysterious black liquid, which was video recorded being dumped into the sea near Fort Ricasoli in Kalkara, is being investigated by the Environment and Resources Authority.

Watch: Video of black liquid streaming into the sea at Ricasoli goes viral

Dr Deidun, an ERA board member, yesterday told the Times of Malta the authorities should ensure that any liquid being dumped is as clean as possible.

He said he had first raised the issue back in 2014 when the Ricasoli Tank Cleaning Facility had been found dumping a sulphur rich liquid that was the by-product of waste oil treatment activities.

The facility, he said, had been allowed to continue dumping the liquid in the area frequented by bathers, as no alternative had been provided.

“I expect the facility to at least introduce a better treatment process, to ensure that the liquid left over is as close to clean water as possible,” he said.

Video footage of what appeared to be dumping of industrial waste by the oil tank cleaning company went viral on social media this week, with dozens of users expressing their outrage at the blatant pollution of the marine and coastal environment.

ERA board member first raised the issue back in 2014

In the video uploaded to Facebook, the black liquid can be seen streaming into the sea at a steady rate. 

An ERA spokesperson has confirmed that the discharge came from the Ricasoli Tank Cleaning Facility.

“ERA compliance officers ordered the facility to cease all activities with immediate effect, following which the discharge was confirmed to have stopped,” the spokesperson had said. 

He did not specify whether the discharge was oil, despite being pressed on the issue. 

The tank cleaning facility is operated by Waste Oil Limited, which was handed a 30-year lease to manage the facility in 2013.

Two years ago this newspaper revealed how a similar pipe had been attached to the foot of the Ricasoli bastions and was discharging a black liquid that gave off a strong smell of fuel.

At the time, Waste Oils Limited concluded that it “cannot provide” a rational explanation for the black effluent being discharged into the sea.

Although a reason for the discharge could not be given at the time, the company had said that the increased use of water to clean tanks, after the authorities had banned it from using certain chemicals, could have resulted in an overflow of waste fluids into the sea.

Marine biologist Victor Axiak had called for independent water tests to verify the company’s claims.

Prof. Axiak now heads the ERA.

Questions sent to ERA on the matter remain unanswered. Falzon Group, who also did not reply to questions, owns Waste Oils Limited.